Mobile station apparatus, base station apparatus, communication method and communication system

ABSTRACT

In the case that periodical transmission of transmission signal number-of-sequence quality indicative signal cannot be performed, the number of transmission signal sequences is clarified in association with reception quality information that is generated immediately after the case, and the base station apparatus performs appropriate communication resource allocation. A mobile station apparatus has a feedback information control section  65  that generates feedback information including reception quality information, transmission signal preprocessing information and transmission signal number-of-sequence information, and a radio transmission section  51  that periodically transmits the generated feedback information to the base station apparatus, where when the radio transmission section  51  does not transmit the transmission signal number-of-sequence information with communication resources periodically allocated from the base station apparatus so as to transmit the transmission signal number-of-sequence information, the radio transmission section  51  transmits the transmission signal number-of-sequence information to the base station apparatus with communication resources enabling transmission of the feedback information allocated from the base station apparatus subsequently to the communication resources.

TECHNICAL FIELD

The present invention relates to techniques where a mobile stationapparatus and base station apparatus perform radio communications usingall or a part of a plurality of antennas.

BACKGROUND ART

3GPP (3rd Generation Partnership Project) is a project for discussingand preparing specifications of cellular telephone systems based onnetworks of evolved W-CDMA (Wideband-Code Division Multiple Access) andGSM (Global System for Mobile Communications). In 3GPP, the W-CDMAsystem has been standardized as the 3rd-generation cellular mobilecommunication system, and its service is started sequentially. Further,HSDPA (High-Speed Downlink Packet Access) with further increasedcommunication rates has also been standardized, and its service isstarted. 3GPP is discussing evolution of the 3rd-generation radio accesstechnique (Evolved Universal Terrestrial Radio Access: hereinafter,referred to as “E-UTRA”).

As a downlink communication system in E-UTRA, proposed is an OFDMA(Orthogonal Frequency Division Multiple Access) system for multiplexingusers using mutually orthogonal subcarriers. Further, in the OFDMAsystem are applied techniques such as an adaptivemodulation/demodulation-error correcting scheme (AMCS: AdaptiveModulation and Coding Scheme) based on adaptive radio link control suchas channel coding, etc.

AMCS is a scheme for switching radio transmission parameters such as acoding rate of error correction, the level of data modulation, etc.corresponding to propagation path conditions of each mobile stationapparatus so as to efficiently perform high-speed packet datatransmission. For example, data modulation is switched to a multilevelmodulation scheme with higher modulation efficiency such 16QAM(Quadrature Amplitude Modulation), 64QAM, etc. from QPSK (QuadraturePhase Shift Keying) as the propagation path conditions are better, andit is thereby possible to increase maximum throughput in the mobilecommunication system.

In OFDMA, it is possible to physically divide the communicable region inthe frequency domain corresponding to subcarriers and time domain. Acombination of some divided regions is referred to as a resource block,one or more resource blocks are allocated to each mobile stationapparatus, and communications are performed while multiplexing aplurality of mobile station apparatuses.

In order that the base station apparatus and each mobile stationapparatus perform communications with optimal quality and rate inresponse to the request, required is resource block allocation andtransmission scheme determination with consideration given to thereception quality in each subcarrier in the mobile station apparatus.Since the base station apparatus determines the transmission scheme andscheduling, and only the mobile station apparatus knows downlinkpropagation path conditions in Frequency Division Duplex, to achieve therequest, each mobile station apparatus is required to give feedback ofreception quality (corresponding to MCS (Modulation-Error correctingcoding scheme) receivable in the mobile station) to base stationapparatus. The reception quality of each mobile station apparatus is fedback to the base station apparatus by using CQI (Channel QualityIndicator).

Further, to increase the communication path capacity in E-UTRA, the useof transmission diversity has been proposed such as SM (SpaceMultiplexing) technique using MIMO (Multiple Input Multiple Output),SFBC (Space-Frequency Block Code) and the like. By using MIMO, it ispossible to form a plurality of propagation paths as a space due to theeffect of multipath, and multiplex a plurality of pieces of informationto transmit. On the reception side, it is possible to combine power of aplurality of transmission antennas to obtain the reception gain. Herein,these techniques are collectively referred to as MIMO. In E-UTRA, it isassumed to use SM by MIMO and transmission diversity on downlink, andthe scheme to perform communications is determined in consideration ofpropagation path conditions between the base station apparatus andmobile station apparatus.

In using MIMO-SM, to facilitate separation processing of a plurality ofspace multiplexed sequences transmitted from antennas, it is consideredthat the base station apparatus beforehand performs preprocessing ontransmission signal sequences. The information of the transmissionsignal preprocessing cannot be calculated in the base station apparatus,and each mobile station apparatus needs to transmit the transmissionsignal preprocessing information to the base station apparatus asfeedback in MIMO-SM communication.

Further, in MIMO-SM, the information of the number of spatiallymultiplexed signal sequences is also dependent on the propagation pathbetween the mobile station apparatus and base station apparatus, and iscalculated in the mobile station apparatus based on a reference signaltransmitted from the base station apparatus. In other words, each mobilestation apparatus needs to give feedback of this information to the basestation apparatus as well as the above-mentioned feedback information.

As described above, to achieve MIMO-SM communication, each mobilestation apparatus is required to transmit three kinds of informationi.e. the reception quality information, transmission signalpreprocessing information, and transmission signal number-of-sequenceinformation as feedback for the communication path with the base stationapparatus. The number of bits, format and transmission frequencyrequired to give each feedback are different from one another, and arevaried in a respective period corresponding to propagation pathconditions and conditions of the mobile station apparatus.

More specifically, time variations are more moderate in the optimalnumber of sequences of transmission signals than in the transmissionsignal preprocessing information. When scheduling is performed to alwaysconcurrently transmit the optimal number of sequences of transmissionsignals and the transmission signal preprocessing information, andfeedback is performed in accordance with the transmission period of thetransmission signal preprocessing information, the number of sequencesof transmission signals that is not varied undergoes feedback manytimes, and as a result, overhead arises in uplink resources. Meanwhile,when feedback is performed in accordance with the transmission period ofthe number of sequences of transmission signals, information of thetransmission signal preprocessing information is insufficient in thebase station apparatus. As a result, MIMO communication is performed bythe preprocessing that is not suitable for the transmission signal, andsystem throughput decreases.

Further, the information amounts of the reception quality informationand transmission signal preprocessing information are varied with thenumber of transmission signal sequences. More specifically, whendifferent modulation schemes are applied for each transmission signalsequence, the reception quality information is required corresponding tothe number of sequences. Further, the transmission signal preprocessinginformation is information represented by a matrix corresponding to thenumber of transmission signal sequences and the number of transmissionantennas, and the number of required bits varies according to the numberof transmission signal sequences. From such a feature, it is effectiveto transmit the number of transmission signal sequences fast among theabove-mentioned feedback information, and to subsequently transmit thereception quality information and transmission signal preprocessinginformation corresponding to the reception quality information.

FIG. 11 contains a timing chart and sequence chart showing the flow ofprocessing between the base station apparatus and mobile stationapparatus in the conventional mobile communication system. An example asshown in FIG. 11 is to implement a mechanism as described in Non-patentDocument to periodically transmit the reception quality information,transmission signal preprocessing information and the number oftransmission signal sequences, is an example of transmitting each kindof feedback information on a periodically assigned uplink controlchannel (PUCCH: Physical Uplink Control Channel), and describes feedbackof from subframes 1 to 16.

Herein, to simplify, omitted are downlink signals, uplink data signals,and feedback information such as ACK/NACK (PositiveAcknowledgement/Negative Acknowledgement) transmitted to the basestation apparatus from the mobile station apparatus, and the like. Inthis example, resources of the uplink control channel are allocatedbefore subframe 1, and starting from subframe 1, resources are allocatedevery three subframes (710). For the reception quality information,transmission signal preprocessing information and the number oftransmission signal sequences transmitted using the resources, theirtransmission timings are shown in “711”.

The base station apparatus notifies the mobile station apparatus ofinformation about the number of times once which the number oftransmission signal sequences is transmitted in the resources, and inthis example, it is set that such information is transmitted once everyfour times in allocated resources. In other words, the number oftransmission signal sequences is periodically transmitted in subframes 1and 13, and it is assumed that the numbers of transmission signalsequences are “3” and “4” respectively (steps S701, S705). In remainingresources i.e. in subframes 4, 7, 10 and 16, the reception qualityinformation and transmission signal preprocessing information isperiodically transmitted (steps S702, 703, S704, S706).

At this point, the reception quality information and transmission signalpreprocessing information is corresponding to the last transmittednumber of transmission signal sequences. In other words, transmitted insubframes 4, 7 and 10 is the reception quality information andtransmission signal preprocessing information corresponding to thenumber of transmission signal sequences transmitted in the subframe 1i.e. “3”. Transmitted in a subframe 16 is the reception qualityinformation and transmission signal preprocessing informationcorresponding to the number of transmission signal sequences transmittedin a subframe 13 i.e. “4”.

Meanwhile, in E-UTRA, to suppress power consumption in the mobilestation apparatus, there is a technique of DRX (Discontinuous Reception)that the power is turned on only for the duration required by the mobilestation apparatus to receive signals. FIG. 12 is a diagram showing theoutline of DRX control. The mobile station apparatus repeats on-duration802 and opportunity for DRX 803 in a DRX cycle 801 (repetition cycle).When the on-duration and DRX cycle are configured, the opportunity forDRX is uniquely determined. The on-duration is a period of time formedof one or more subframes defined to monitor PDCCH.

In the on-duration, the base station apparatus transmits PDCCH to startuplink or downlink resource allocation. A mobile station apparatusreceiving PDCCH indicative of scheduling of uplink or downlink initialtransmission data (new data) in the on-duration monitors PDCCH for apredetermined duration after the on-duration (804). Further, for aduration having the possibility of retransmission of uplink data ordownlink data, the mobile station apparatus monitors PDCCH irrespectiveof whether the duration is in or out of the on-duration range (805). Theduration is referred to as Active Time during which the receivingsection of the mobile station apparatus is started and active to monitorPDCCH (806).

The base station apparatus transmits data during the Active Time of themobile station apparatus. The base station apparatus beforehand notifiesthe mobile station apparatus of the repetition period and on-duration ofthe DRX cycle, and the mobile station apparatus beforehand repeatspower-on periodically based on the information, while performingpower-on corresponding to reception conditions of PDCCH and dataretransmission conditions (see Non-patent Document 2).

Described next is an example of feedback as shown in Non-patent Document1 with the aforementioned DRX considered. FIG. 13 contains a timingchart and sequence chart showing the flow of processing between the basestation apparatus and mobile station apparatus in the conventionalmobile communication system. DRX is shown in “912” in FIG. 13, andsubframes 6 to 14 correspond to the duration (herein, referred to asNon-active Time) except the Active Time. As shown in “910”, resources ofeach kind of feedback information are allocated in subframes 1, 4, 7,10, 13 and 16 as in the example of FIG. 11, and the base stationapparatus sets the transmission signal number-of-sequence information tobe transmitted at a frequency of once every four times in the allocatedresources.

In other words, feedback is set to transmit the transmission signalnumber-of-sequence information in subframes 1 and 13 and the receptionquality information and transmission signal preprocessing information insubframes 4, 7, 10 and 16. In addition, in order to halt feedback inaccordance with the Non-active Time of DRX notified from the basestation apparatus, feedback from the mobile station apparatus is givenonly in subframes 1, 14 and 16, and transmitted as feedback is thetransmission signal number-of-sequence information (step S901), thereception quality information and transmission signal preprocessinginformation (step S902), and the reception quality information andtransmission signal preprocessing information (step S903).

However, transmission of the number of transmission signal sequences inthe subframe 13 corresponding to the subframe 16 (step S903) is in theNon-active Time, and there is the problem that the base stationapparatus cannot know information that the reception quality informationand transmission signal preprocessing information transmitted in thesubframe 16 (step S903) corresponds to which number of transmissionsignal sequences. Non-patent Document 2 describes calculating andtransmitting the reception quality information and transmission signalpreprocessing information according to the last transmitted number oftransmission signal sequences, but when the opportunity for DRX is largewith respect to a rate of change in propagation path, the possibility ishigh that the number of transmission signal sequences is varied from theoptimal number, and as a result, there is the fear of reducingthroughput characteristics.

Further, as in the case of not transmitting the number of transmissionsignal sequences due to DRX, such a case arises that the number oftransmission signal sequences cannot be transmitted because it isnecessary to transmit another information with a higher priority attiming scheduled to transmit the number of transmission signalsequences.

[Non-patent Document 1] Summary of AH on AI 6.3.4 “UE Procedures fordownlink shared channel”, 3GPP TSG-RAN WG1 Meeting #52, R1-081137[Non-patent Document 2] 3GPP TS 36.321 V8.0.0 (2007-12) TechnicalSpecification 3rd Generation Partnership Project; TechnicalSpecification Group Radio Access Network; Evolved Universal TerrestrialRadio Access (E-UTRA) Medium Access Control (MAC) protocol specification(Release 8)

DISCLOSURE OF INVENTION Problems to be Solved by the Invention

However, in the aforementioned conventional techniques, for example,when the transmission timing of the transmission signalnumber-of-sequence information that is transmitted periodically from themobile station apparatus is made transmission disabled due to a reasonof Discontinuous Reception or the like, the transmission signalnumber-of-sequence information is not transmitted, and there is theproblem that the base station apparatus does not know which number oftransmission signal sequences is associated with the reception qualityinformation that is received immediately after the DiscontinuousReception.

In this case, it is considered that the mobile station apparatustransmits the reception quality information according to thetransmission signal number-of-sequence information transmittedimmediately before Discontinuous Reception starts. However, for example,when the moving speed of the mobile station apparatus is fast, a changeoccurs in the propagation path conditions under circumstances where thetransmission signal number-of-sequence information cannot betransmitted, the suitable number of transmission signal sequences isalso varied according to the change, the reception quality informationitself loses reliability, and there is the problem that downlinkreception characteristics deteriorate.

The present invention was made in view of such circumstances, and it isan object of the invention to provide a mobile station apparatus, basestation apparatus, communication method and communication system forclarifying the number of transmission signal sequences in associationwith reception quality information that is generated immediately afterthe case where periodical transmission of transmission signalnumber-of-sequence quality indicative signal cannot be performed, andenabling the base station apparatus to perform appropriate communicationresource allocation.

Means for Solving the Problem

(1) To attain the above-mentioned object, the present invention tookmeasures as described below. In other words, a mobile communicationsystem of the invention is a mobile communication system in which amobile station apparatus periodically transmits transmission signalnumber-of-sequence information and reception quality informationcalculated based on the transmission signal number-of-sequenceinformation to the base station apparatus, and is characterized in thatthe mobile station apparatus calculates the reception qualityinformation based on the beforehand determined number of transmissionsignal sequences when the transmission signal number-of-sequenceinformation is not transmitted to the base station apparatus, and thatthe base station apparatus processes the reception quality informationbased on the beforehand determined number of transmission signalsequences when the transmission signal number-of-sequence information isnot transmitted.

(2) Further, in the mobile communication system of the invention, it isa feature that the beforehand determined number of transmission signalsequences is the minimum number of transmission signal sequences.

(3) Furthermore, in the mobile communication system of the invention, itis another feature that the beforehand determined number of transmissionsignal sequences is the maximum number of transmission signal sequences.

(4) Further, a mobile communication system of the invention is a mobilecommunication system in which a mobile station apparatus periodicallytransmits transmission signal number-of-sequence information andtransmission signal preprocessing information calculated based on thetransmission signal number-of-sequence information to a base stationapparatus, and is characterized in that the mobile station apparatuscalculates the transmission signal preprocessing information based onthe beforehand determined number of transmission signal sequences whenthe transmission signal number-of-sequence information is nottransmitted to the base station apparatus, and that the base stationapparatus processes the transmission signal preprocessing informationbased on the beforehand determined number of transmission signalsequences when the transmission signal number-of-sequence information isnot transmitted.

(5) Furthermore, in the mobile communication system of the invention, itis a feature that the beforehand determined number of transmissionsignal sequences is the minimum number of transmission signal sequences.

(6) Still furthermore, in the mobile communication system of theinvention, it is another feature that the beforehand determined numberof transmission signal sequences is the maximum number of transmissionsignal sequences.

(7) Further, a base station apparatus of the invention is a base stationapparatus that periodically receives transmission signalnumber-of-sequence information and reception quality information that iscalculated in a mobile station apparatus based on the transmissionsignal number-of-sequence information from the mobile station apparatus,and is characterized by having means for processing the receptionquality information based on the beforehand determined number oftransmission signal sequences when the transmission signalnumber-of-sequence information is not transmitted.

(8) Furthermore, in the base station apparatus of the invention, it is afeature that the beforehand determined number of transmission signalsequences is the minimum number of transmission signal sequences.

(9) Still furthermore, in the base station apparatus of the invention,it is another feature that the beforehand determined number oftransmission signal sequences is the maximum number of transmissionsignal sequences.

(10) Further, a base station apparatus of the invention is a basestation apparatus that periodically receives transmission signalnumber-of-sequence information and transmission signal preprocessinginformation that is calculated in a mobile station apparatus based onthe transmission signal number-of-sequence information from the mobilestation apparatus, and is characterized by having means for processingthe transmission signal preprocessing information based on thebeforehand determined number of transmission signal sequences when thetransmission signal number-of-sequence information is not transmitted.

(11) Furthermore, in the base station apparatus of the invention, it isa feature that the beforehand determined number of transmission signalsequences is the minimum number of transmission signal sequences.

(12) Still furthermore, in the base station apparatus of the invention,it is another feature that the beforehand determined number oftransmission signal sequences is the maximum number of transmissionsignal sequences.

(13) Further, a mobile station apparatus of the invention is a mobilestation apparatus that periodically transmits transmission signalnumber-of-sequence information and reception quality informationcalculated based on the transmission signal number-of-sequenceinformation to a base station apparatus, and is characterized by havingmeans for calculating the reception quality information based on thebeforehand determined number of transmission signal sequences when thetransmission signal number-of-sequence information is not transmitted.

(14) Furthermore, in the mobile station apparatus of the invention, itis a feature that the beforehand determined number of transmissionsignal sequences is the minimum number of transmission signal sequences.

(15) Still furthermore, in the mobile station apparatus of theinvention, it is another feature that the beforehand determined numberof transmission signal sequences is the maximum number of transmissionsignal sequences.

(16) Further, a mobile station apparatus of the invention is a mobilestation apparatus that periodically transmits transmission signalnumber-of-sequence information and transmission signal preprocessinginformation calculated based on the transmission signalnumber-of-sequence information to a base station apparatus, and ischaracterized by having means for calculating the transmission signalpreprocessing information based on the beforehand determined number oftransmission signal sequences when the transmission signalnumber-of-sequence information is not transmitted.

(17) Furthermore, in the mobile station apparatus of the invention, itis a feature that the beforehand determined number of transmissionsignal sequences is the minimum number of transmission signal sequences.

(18) Still furthermore, in the mobile station apparatus of theinvention, it is another feature that the beforehand determined numberof transmission signal sequences is the maximum number of transmissionsignal sequences.

ADVANTAGEOUS EFFECT OF THE INVENTION

According to the invention, when the transmission signalnumber-of-sequence information is not transmitted with communicationresources periodically allocated by the base station apparatus so as totransmit the transmission signal number-of-sequence information, thetransmission signal number-of-sequence information is transmitted to thebase station apparatus with communication resources enabling thefeedback information to be transmitted allocated by the base stationapparatus subsequently to the communication resources. Therefore, forexample, even when the mobile station apparatus cannot transmit feedbackof the transmission signal number-of-sequence information to the basestation apparatus because a subframe that is the transmission timing ofthe transmission signal number-of-sequence information is in a period ofNon-active Time of DRX, the mobile station apparatus can give feedbackin a subframe with uplink control channel resource allocation subsequentto the end of the Non-active Time of DRX. By this means, the basestation apparatus is able to know the correct transmission signalnumber-of-sequence information after the end of the Non-active Time ofDRX, and is able to perform appropriate downlink communication resourceallocation based on the subsequently transmitted reception qualityinformation and transmission signal preprocessing information.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram showing a configuration example of a basestation apparatus according to Embodiments of the invention;

FIG. 2 is a block diagram showing a configuration example of a mobilestation apparatus according to Embodiments of the invention;

FIG. 3 is a diagram showing a timing chart to explain the flow ofprocessing between the base station apparatus and mobile stationapparatus in a mobile communication system according to Embodiment 1;

FIG. 4 is a sequence chart between the base station apparatus and mobilestation apparatus in the mobile communication system according toEmbodiment 1;

FIG. 5 is a diagram showing a timing chart to explain the flow ofprocessing between the base station apparatus and mobile stationapparatus in a mobile communication system according to Embodiment 2;

FIG. 6 is a sequence chart between the base station apparatus and mobilestation apparatus in the mobile communication system according toEmbodiment 2;

FIG. 7 is a diagram showing a timing chart to explain the flow ofprocessing between the base station apparatus and mobile stationapparatus in a mobile communication system according to Embodiment 3;

FIG. 8 is a sequence chart between the base station apparatus and mobilestation apparatus in the mobile communication system according toEmbodiment 3;

FIG. 9 is a diagram showing a timing chart to explain the flow ofprocessing between the base station apparatus and mobile stationapparatus in a mobile communication system according to Embodiment 4;

FIG. 10 is a sequence chart between the base station apparatus andmobile station apparatus in the mobile communication system according toEmbodiment 4;

FIG. 11 contains a timing chart and sequence chart showing the flow ofprocessing between a base station apparatus and mobile station apparatusin a conventional mobile communication system;

FIG. 12 is a diagram showing the outline of DRX control; and

FIG. 13 contains another timing chart and sequence chart showing theflow of processing between the base station apparatus and mobile stationapparatus in the conventional mobile communication system.

DESCRIPTION OF SYMBOLS

-   1 Data control section-   3 Modulation coding section-   4 Transmission signal preprocessing section-   5 Mapping section-   7 Inverse Fast Fourier Transform (IFFT) section-   11 Radio transmission section-   12 Antenna-   15 Radio reception section-   17 Fast Fourier Transform (FFT) section-   21 Inverse Discrete Fourier Transform (IDFT) section-   22 Demodulation decoding section-   23 Data extraction section-   25 Scheduler section-   27 Transmission information control section-   31 Modulation code control section-   33 Frequency selection scheduler section-   35 Transmission signal number-of-sequence information control    section-   36 Transmission signal preprocessing information control section-   41 Data control section-   43 Modulation coding section-   44 Discrete Fourier Transform (DFT) section-   45 Mapping section-   47 Inverse Fast Fourier Transform (IFFT) section-   51 Radio transmission section-   53 Radio reception section-   55 Fast Fourier Transform (FFT) section-   57 Demodulation decoding section-   61 Data extraction section-   63 Antenna-   65 Feedback information control section-   67 Reception quality information generating section-   68 Transmission signal preprocessing information generating section-   69 Transmission signal number-of-sequence information generating    section-   71 Reception quality measuring section

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the invention will specifically be described below withreference to drawings. In addition, in the following description, theinvention is embodied using a mobile communication system, but is notlimited thereto, and is achieved as a mobile communication method.

Embodiment 1

A mobile communication system according to Embodiment 1 of the inventionis comprised of base station apparatuses and mobile station apparatuses.FIGS. 1 and 2 are block diagrams showing configuration examples of thebase station apparatus and the mobile station apparatus according tothis Embodiment, respectively. As shown in FIG. 1, the base stationapparatus is provided with a data control section 1, modulation codingsection 3, transmission signal preprocessing section 4, mapping section5, Inverse Fast Fourier Transform (IFFT) section 7, radio transmissionsection 11, radio reception section 15, Fast Fourier Transform (FFT)section 17, Inverse Discrete Fourier Transform (IDFT) section 21,demodulation decoding section 22, data extraction section 23,transmission information control section 27, and antenna 12.

The transmission information control section 27 includes a schedulersection 25, modulation code control section 31, frequency selectionscheduler section 33, transmission signal number-of-sequence informationcontrol section 35, and transmission signal preprocessing informationcontrol section 36. The antenna 12 has the number of antennas requiredfor MIMO-SDM communication.

The data control section 1 receives transmission data and control datato transmit to each mobile station apparatus, and each data issequentially transmitted to the mobile station apparatus according todirections from the transmission information control section 27. WhenMIMO-SDM is applied to output data, the data is divided into a pluralityof transmission sequences according to information of the transmissionsignal number-of-sequence information control section 35.

The modulation coding section 3 performs modulation processing and errorcorrecting coding processing on a signal input from the data controlsection 1, based on a modulation scheme and coding rate by thetransmission information control section 27, and outputs the resultantsignal to the transmission signal preprocessing section 4. Thetransmission signal preprocessing section 4 processes the signal inputfrom the modulation coding section 3 based on control information inputfrom the transmission information control section 27, and outputs theresultant signal to the mapping section 5.

The mapping section 5 performs mapping of data output from themodulation coding section 3 on each subcarrier based on frequencyselection scheduling information input from the transmission informationcontrol section 27, and outputs the resultant signal to the Inverse FastFourier Transform section 7. The Inverse Fast Fourier Transform section7 performs processing of Inverse Fast Fourier Transform on the dataoutput from the mapping section 5 to transform into a time-seriesbaseband digital signal, and outputs the resultant signal to the radiotransmission section 11.

The output signal from the Inverse Fast Fourier Transform section 7undergoes digital/analog conversion in the radio transmission section11, is up-converted into a signal with a frequency suitable fortransmission, and transmitted to each mobile station apparatus via theantenna 12.

The scheduler section 25 performs downlink scheduling and uplinkscheduling based on control information such as a resource area usablefor each mobile station apparatus, intermittent transmission/receptioncycle, format of a transmission data channel, buffer status and thelike, while performing control of varying the number of transmissionsignal sequences. The modulation code control section 31 determines amodulation scheme and coding rate applied to each data based onreception quality information transmitted from the mobile stationapparatus.

The frequency selection scheduler section 33 performs processing offrequency selection scheduling applied to each data, based on thefeedback information transmitted from the mobile station apparatus. Thetransmission signal number-of-sequence information control section 35determines the number of sequences of transmission signals, based on thetransmission signal number-of-sequence information transmitted from themobile station apparatus, traffic status of the base station apparatusand the like. The transmission signal preprocessing information controlsection 36 determines preprocessing to apply to the transmission databased on the transmission signal preprocessing information transmittedfrom the mobile station apparatus.

The transmission information control section 27 controls operations ofthe scheduler section 25, modulation code control section 31, frequencyselection scheduler section 33, transmission signal number-of-sequenceinformation control section 35, transmission signal preprocessinginformation control section 36, and transmission information controlsection 27, using control information input from the higher layer andcontrol information input from the data extraction section 23. Thesection 27 manages the output information of each section to outputcontrol information required for operations of the data control section1, modulation coding section 3, transmission signal preprocessingsection 4 and mapping section 5.

The radio reception section 15 performs analog/digital conversion on asignal received in the antenna 12 to down-covert into a baseband signal,and outputs the resultant signal to the Fast Fourier Transform (FFT)section 17. The Fast Fourier Transform (FFT) section 17 performs Fouriertransform on the reception signal on a unit processing time basis tooutput to the Inverse Discrete Fourier Transform section 21. The InverseDiscrete Fourier Transform section 21 divides the input signal intobands assigned to respective mobile station apparatuses to performInverse Fourier transform processing, and outputs a reproduced SC-FDMAsignal to the demodulation decoding section 22.

The demodulation decoding section 22 performs demodulation and decodingon the input signal for each mobile station apparatus to output to thedata extraction section 23. The data extraction section 23 divides thesignal input from the demodulation decoding section 22 into informationrequired for control information generation in the transmissioninformation control section 27, reception data, and control datarequired for the higher layer to output.

Meanwhile, as shown in FIG. 2, the mobile station apparatus is providedwith a data control section 41, modulation coding section 43, DiscreteFourier Transform (DFT) section 44, mapping section 45, Inverse FastFourier Transform (IFFT) section 47, radio transmission section 51,radio reception section 53, Fast Fourier Transform (FFT) section 55,demodulation decoding section 57, data extraction section 61, andantenna 63. A feedback information control section 65 has a receptionquality information generating section 67, reception quality measuringsection 71, transmission signal preprocessing information generatingsection 68, and transmission signal number-of-sequence informationgenerating section 69. The antenna 63 is provided with the number ofantennas required for MIMO-SDM communication.

The data control section 41 receives transmission data, control data andfeedback information output from the feedback information controlsection 65 each to transmit to the base station apparatus, and each datais sequentially transmitted to the base station apparatus.

The modulation coding section 43 performs modulation processing anderror correcting coding processing on the signal input from the datacontrol section 41, and outputs each data to the Discrete FourierTransform section 44. The Discrete Fourier Transform section 44 performsFourier transform processing on the signal input from the modulationcoding section 43, and generates a signal to perform SC-FDMA to outputto the mapping section 45. The mapping section 45 performs mapping ofthe data input from the Discrete Fourier Transform section 44 onsubcarriers assigned by the base station apparatus to output to theInverse Fast Fourier Transform section 47.

The Inverse Fast Fourier Transform section 47 performs processing ofInverse Fast Fourier Transform on a symbol sequence input from themapping section 45 to transform into a time-series baseband digitalsignal, and outputs the resultant signal to the radio transmissionsection 51. The output signal from the Inverse Fast Fourier Transformsection 47 undergoes digital/analog conversion in the radio transmissionsection 51, is up-converted into a signal with a frequency suitable fortransmission, and transmitted to the base station apparatus via theantenna.

The reception quality measuring section 71 measures reception quality ofa signal received from the base station apparatus. Based on theinformation measured by the reception quality measuring section 71, thereception quality information generating section 67 generates receptionquality information to transmit to the base station apparatus. Thetransmission signal preprocessing information generating section 68calculates propagation path information using a signal received from thebase station apparatus, and generates information of preprocessing on atransmission signal to be performed by the base station apparatus. Thetransmission signal number-of-sequence information generating section 68calculates propagation path information using a signal received from thebase station apparatus, and calculates the number of transmissionsequences communicable with the base station apparatus.

The feedback information control section 65 manages control signalsgenerated in the reception quality information generating section 67,transmission signal preprocessing information generating section 68, andtransmission signal number-of-sequence information generating section 69to output to the data control section 41. The feedback informationmanaged in the feedback information control section 65 is not limited togeneration and control of the signals described herein, and may includeportions to manage other kinds of feedback information.

FIG. 3 is a diagram showing a timing chart to explain the flow ofprocessing between the base station apparatus and mobile stationapparatus in a mobile communication system according to Embodiment 1.FIG. 4 is a sequence chart between the base station apparatus and mobilestation apparatus in the mobile communication system according toEmbodiment 1. As shown in FIGS. 3 and 4, the reception qualityinformation, transmission signal preprocessing information andtransmission signal number-of-sequence information is transmitted onlyin subframes subjected to uplink control channel resource allocationthat is performed by the base station apparatus on the mobile stationapparatus. Further, herein, it is possible to concurrently transmit thereception quality information and transmission signal preprocessinginformation, but transmission signal number-of-sequence information isnot transmitted concurrently with the reception quality information andtransmission signal preprocessing information. In addition, in FIGS. 3and 4, as an example, the uplink control channel resource allocation ismade every three subframes, the transmission signal number-of-sequenceinformation is transmitted once every four times the uplink controlchannel resource allocation is performed, and the reception qualityinformation and transmission signal preprocessing information isperiodically transmitted at the other uplink control channel resourceallocation times.

The operation of the mobile communication system according to thisEmbodiment will be described below with reference to FIGS. 3 and 4. Thebase station apparatus is able to allocate uplink control channelresources for the mobile station apparatus to transmit the receptionquality information, transmission signal preprocessing information andtransmission signal number-of-sequence information permanently for thelong term, for example, using a radio resource control signal (RRCsignaling). First, the mobile station apparatus transmits thetransmission signal number-of-sequence information to the base stationapparatus as feedback in a subframe 1 first assigned uplink controlchannel resources (step S41). Herein, the mobile station apparatustransmits the transmission signal number-of-sequence information fromthe subframe 1, and a subframe in which the mobile station apparatusstarts transmitting reception quality information, transmission signalpreprocessing information and transmission signal number-of-sequenceinformation can be set using an offset value transmitted from the basestation apparatus.

In a subframe 4 in which next uplink control channel allocation isperformed, the mobile station apparatus transmits to the base stationapparatus the reception quality information and the transmission signalpreprocessing information based on the transmission signalnumber-of-sequence information (=3) transmitted to the base stationapparatus in the subframe 1 (step S42). Then, Non-active Time of DRXstarts from a subframe 6, and downlink data transmission from the basestation apparatus to mobile station apparatus is suspended (step S43).In subframes 7 and 10, uplink control channel resource allocation isperformed, but the subframes are in a period of Non-active Time of DRX,and feedback is not given on the reception quality information andtransmission signal preprocessing information.

Next, a subframe 13 is timing of transmitting the transmission signalnumber-of-sequence information as feedback, but is still in the periodof Non-active Time of DRX, and in this subframe, feedback is notperformed (step S43). The mobile station apparatus performs feedback oftransmission signal number-of-sequence information (n=2) in a subframe16 with next uplink control channel resource allocation after the end ofthe Non-active Time of DRX (step F44). Further, the subframe 16 isoriginally the feedback timing of reception quality information andtransmission signal preprocessing information, but in this subframe,since the transmission signal number-of-sequence information istransmitted, feedback is not performed on the reception qualityinformation and transmission signal preprocessing information. Then, insubframes 19 and 22 in which next uplink control channel allocation isperformed, the mobile station apparatus transmits to the base stationapparatus the reception quality information and transmission signalpreprocessing information based on the transmission signalnumber-of-sequence information (=2) transmitted in the subframe 16(steps S45, S46).

Next, in a subframe 25, the mobile station apparatus transmits thetransmission signal number-of-sequence information to the base stationapparatus as feedback (step S47). Then, in subframes 28 and 31 in whichnext resource allocation for uplink control channel is performed, themobile station apparatus transmits to the base station apparatus thereception quality information and transmission signal preprocessinginformation based on the transmission signal number-of-sequenceinformation (=4) transmitted to the base station apparatus in thesubframe 25 (steps S48, S49).

Thus, according to the mobile communication system according toEmbodiment 1 of the invention, even when a subframe that is thetransmission timing of the transmission signal number-of-sequenceinformation is in a period of Non-active Time of DRX and does not enablefeedback of the transmission signal number-of-sequence information,since the transmission signal number-of-sequence information istransmitted in a subframe with next uplink control channel resourceallocation after the end of the Non-active Time of DRX, the base stationapparatus is able to know the correct transmission signalnumber-of-sequence information after the end of the Non-active Time ofDRX, and to perform appropriate downlink communications based on thesubsequently transmitted reception quality information and transmissionsignal preprocessing information.

In addition, in this Embodiment, in the subframe 16, the transmissionsignal number-of-sequence information is transmitted, instead oftransmitting the reception quality information and the transmissionsignal preprocessing information, but it is possible to concurrentlytransmit all of the information. Further, it is described that whetheror not to perform feedback is determined in the Active Time andNon-active Time of DRX, but whether or not to perform feedback may bedetermined in on-duration of DRX and opportunity for DRX.

Embodiment 2

A mobile communication system according to Embodiment 2 of the inventionwill be described below with reference to drawings. In the mobilecommunication system according to Embodiment 2 of the invention, themobile station apparatus sets the number of transmission sequences at apredetermined value and transmits the reception quality information andthe transmission signal preprocessing information corresponding to thisvalue to the base station apparatus as feedback until next feedback oftransmission signal number-of-sequence information is performed afterNon-active Time of DRX ends when feedback of the transmission signalnumber-of-sequence information cannot be performed due to the Non-activeTime of DRX, and in this respect, the system according to Embodiment 2differs from the mobile communication system according to Embodiment 1.In addition, the configurations of the base station apparatus and mobilestation apparatus are the same as in FIGS. 1 and 2.

FIG. 5 is a diagram showing a timing chart to explain the flow ofprocessing between the base station apparatus and mobile stationapparatus in the mobile communication system according to Embodiment 2.FIG. 6 is a sequence chart between the base station apparatus and mobilestation apparatus in the mobile communication system according toEmbodiment 2. As shown in FIGS. 5 and 6, also in the mobilecommunication system according to this Embodiment, the operations ofsubframes 1 to 13 (steps S61 to S63) are the same as the operations inEmbodiment 1, and descriptions thereof are omitted.

Next, the mobile station apparatus performs the following operation fora period during which Non-active Time of DRX ends and next feedback ofthe transmission signal number-of-sequence information (n=4) isperformed in a subframe 25. In other words, in subframes 16, 19 and 22in which uplink control channel resource allocation occurs, the mobilestation apparatus transmits to the base station apparatus the receptionquality information and transmission signal preprocessing informationbased on the predetermined transmission signal number-of-sequenceinformation (steps S64, S65, S66). Herein, the predeterminedtransmission signal number-of-sequence information is, for example, thenumber of transmission signal sequences=1 (minimum value) that minimizesthe information amount of the feedback information from the mobilestation apparatus, or the number of transmission signal sequences=4(maximum value) that enables the propagation path to be used mostefficiently (enables maximum throughput to be obtained) and the like,and can be defined by specifications or the like in advance between thebase station apparatus and mobile station apparatus.

Then, for the reception quality information and transmission signalpreprocessing information sent as feedback for a period during which theNon-active Time of DRX ends and the mobile station apparatus gives nextfeedback of the transmission signal number-of-sequence information, thebase station apparatus performs the processing while regarding thetransmission signal number-of-sequence information as the predeterminedvalue (for example, the number of transmission signal sequences=1(minimum value) or the number of transmission signal sequences=4(maximum value)). Then, after receiving feedback of the transmissionsignal number-of-sequence information (n=4) in the subframe 25 from themobile station apparatus (step S67), the base station apparatus receivesfeedback of the reception quality information and transmission signalpreprocessing information based on the received transmission signalnumber-of-sequence information (=4) in subframes 28 and 31 (steps S68,S69).

In addition, FIGS. 5 and 6 describe setting a predetermined value oftransmission signal number-of-sequence information at “1” as an examplefor a period during which Non-active Time of DRX ends and next feedbackof the transmission signal number-of-sequence information is performed,but as described above, such a value can be defined by specifications orthe like in advance. Further, a case occurs where the transmissionsignal preprocessing information is not necessary such as a case that avalue of transmission signal number-of-sequence information correspondsto transmission diversity of closed loop control. In this case, themobile station apparatus transmits only the reception qualityinformation, and the base station apparatus performs the processing byregarding the reception quality information as being transmitted only.

Thus, according to the mobile communication system according toEmbodiment 2 of the invention, even when a subframe that is thetransmission timing of the transmission signal number-of-sequenceinformation is in a period of Non-active Time of DRX and does not enablefeedback of the transmission signal number-of-sequence information,feedback of the reception quality information and the transmissionsignal preprocessing information is given based on a predetermined valueof the transmission signal number-of-sequence information until themobile station apparatus transmits next feedback of transmission signalnumber-of-sequence information after the Non-active Time of DRX ends,and it is thereby possible to prevent the occurrence of burst error dueto communications using the number of transmission signal sequences thatis not suitable for propagation path conditions.

Embodiment 3

A mobile communication system according to Embodiment 3 of the inventionwill be described below with reference to drawings. In the mobilecommunication system according to Embodiment 3 of the invention, for aperiod during which Non-active Time of DRX ends and next feedback of thetransmission signal number-of-sequence information is performed, themobile station apparatus does not transmit feedback of the receptionquality information and the transmission signal preprocessinginformation to the base station apparatus, and for this period, the basestation apparatus transmits downlink data using the predetermined numberof transmission signal sequences. In this respect, Embodiment 3 differsfrom Embodiments 1 and 2. In addition, the configurations of the basestation apparatus and mobile station apparatus are the same as in FIGS.1 and 2.

FIG. 7 is a diagram showing a timing chart to explain the flow ofprocessing between the base station apparatus and mobile stationapparatus in the mobile communication system according to Embodiment 3.FIG. 8 is a sequence chart between the base station apparatus and mobilestation apparatus in the mobile communication system according toEmbodiment 3. As shown in FIGS. 7 and 8, also in the mobilecommunication system according to this Embodiment, the operations ofsubframes 1 to 13 (steps S81 to S83) are the same as the operations inEmbodiment 1, and descriptions thereof are omitted.

Next, the mobile station apparatus does not perform feedback of thereception quality information and the transmission signal preprocessinginformation for a period during which Non-active Time of DRX ends andnext feedback of the transmission signal number-of-sequence information(n=4) is performed in a subframe 25 even in subframes (subframes 16, 19,22) assigned uplink control channel resources (step S84). The basestation apparatus performs transmission of downlink data inpredetermined form for the period during which Non-active Time of DRXends and next feedback of the transmission signal number-of-sequenceinformation is performed.

More specifically, in a subframe 23, the base station apparatustransmits downlink signal allocation to the mobile station apparatus onthe control channel, and further transmits a downlink signal inresources configured in the allocation. In this subframe, the basestation apparatus transmits the signal using the predetermined number oftransmission signal sequences. Herein, the predetermined form is thenumber of transmission signal sequences=1 (minimum value) that minimizesthe information amount of the feedback information from the mobilestation apparatus, the number of transmission signal sequences=4(maximum value) that enables the propagation path to be used mostefficiently (enables maximum throughput to be obtained) and the like,and can be defined by specifications or the like in advance between thebase station apparatus and mobile station apparatus.

Then, after receiving feedback of the transmission signalnumber-of-sequence information (n=4) in the subframe 25 from the mobilestation apparatus (step S85), the base station apparatus receivesfeedback of the reception quality information and transmission signalpreprocessing information based on the received transmission signalnumber-of-sequence information (=4) in subframes 28 and 31 (steps S86,S87). The base station apparatus implements suitable downlink datatransmission corresponding to the transmission number-of-sequenceinformation, reception quality information and transmission signalpreprocessing information.

Thus, according to the mobile communication system according toEmbodiment 3 of the invention, even when a subframe that is thetransmission timing of the transmission signal number-of-sequenceinformation is in a period of Non-active Time of DRX and does not enablefeedback of the transmission signal number-of-sequence information, fora period during which the Non-active Time of DRX ends and next feedbackof the transmission signal number-of-sequence information is performed,the mobile station apparatus does not perform feedback of the receptionquality information and the transmission signal preprocessinginformation, the base station apparatus transmits downlink data inpredetermined form, and it is thereby possible to reduce consumption ofpower to transmit the feedback information that is not used.

Embodiment 4

A mobile communication system according to Embodiment 4 of the inventionwill be described below with reference to drawings. In the mobilecommunication system according to Embodiment 4 of the invention, for aperiod during which Non-active Time of DRX ends and next feedback of thetransmission signal number-of-sequence information is performed, evenwhen the mobile station apparatus performs feedback of the receptionquality information and the transmission signal preprocessinginformation, the base station apparatus abandons (disables) theinformation and transmits downlink data in predetermined form. In thisrespect, Embodiment 4 differs from Embodiments 1, 2 and 3. In addition,the configurations of the base station apparatus and mobile stationapparatus are the same as in FIGS. 1 and 2.

FIG. 9 is a diagram showing a timing chart to explain the flow ofprocessing between the base station apparatus and mobile stationapparatus in the mobile communication system according to Embodiment 4.FIG. 10 is a sequence chart between the base station apparatus andmobile station apparatus in the mobile communication system according toEmbodiment 4. As shown in FIGS. 9 and 10, also in the mobilecommunication system according to this Embodiment, the operations ofsubframes 1 to 13 (steps S101 to 5103) are the same as the operations inEmbodiment 1, and descriptions thereof are omitted.

Next, the mobile station apparatus performs the following operation fora period during which Non-active Time of DRX ends and next feedback ofthe transmission signal number-of-sequence information is performed in asubframe 25. In other words, in subframes (subframes 16, 19 and 22) inwhich uplink control channel resource allocation is performed, themobile station apparatus transmits to the base station apparatus thereception quality information and transmission signal preprocessinginformation based on the last feedback (subframe 1) of transmissionsignal number-of-sequence information (=3) (step S104). For the periodduring which Non-active Time of DRX ends and next feedback of thetransmission signal number-of-sequence information is transmitted fromthe mobile station apparatus, the base station apparatus disables andabandons the reception quality information and transmission signalpreprocessing information fed back by the mobile station apparatus, andperforms transmission of downlink data in predetermined form (stepS104).

More specifically, in a subframe 23, the base station apparatustransmits downlink signal allocation to the mobile station apparatus onthe control channel, and further transmits a downlink signal in theresources configured in the allocation. In this subframe, the basestation apparatus abandons the received number of transmission signalsequences, and transmits the signal using the predetermined number oftransmission signal sequences. Herein, the predetermined form is thenumber of transmission signal sequences=1 (minimum value) that minimizesthe information amount of the feedback information from the mobilestation apparatus, the number of transmission signal sequences=4(maximum value) that enables the propagation path to be used mostefficiently (enables maximum throughput to be obtained) and the like,and can be defined by specifications or the like in advance between thebase station apparatus and mobile station apparatus.

Then, after receiving feedback of the transmission signalnumber-of-sequence information (n=4) in the subframe 25 (step S105) fromthe mobile station apparatus, the base station apparatus receivesfeedback of the reception quality information and transmission signalpreprocessing information based on the received transmission signalnumber-of-sequence information (=4) in subframes 28 and 31 (steps S106,S107). The base station apparatus performs suitable downlink datatransmission according to the transmission number-of-sequenceinformation, reception quality information and transmission signalpreprocessing information.

Thus, according to the mobile communication system according toEmbodiment 4 of the invention, even when a subframe that is thetransmission timing of the transmission signal number-of-sequenceinformation is in a period of Non-active Time of DRX and does not enablefeedback of the transmission signal number-of-sequence information, fora period during which the Non-active Time of DRX ends and next feedbackof the transmission signal number-of-sequence information is performed,even in the case that the mobile station apparatus performs feedback ofthe reception quality information and the transmission signalpreprocessing information, the base station apparatus transmits downlinkdata in predetermined form. It is thereby possible to prevent theoccurrence of burst error due to communications using the number oftransmission signal sequences that is not suitable for propagation pathconditions.

Embodiment 5

Embodiments 1 to 4 as described above show the case as an example thatDRX causes the reason of occurrence of the situation that the mobilestation apparatus cannot feedback the transmission signalnumber-of-sequence information, but the reason is not limited to DRX.Also when the situation occurs that the transmission signalnumber-of-sequence information cannot be transmitted due to reasonsother than the DRX, the mobile station apparatus and base stationapparatus are able to apply Embodiments 1 to 4 as described above. Forexample, when such a situation occurs that the mobile station apparatuscannot transmit the transmission signal number-of-sequence informationbecause of transmitting a signal (hereinafter, referred to as ascheduling request) for requesting resource allocation to the basestation apparatus, it is possible to apply Embodiments 1 to 4 asdescribed above. When such a situation occurs that the mobile stationapparatus cannot transmit the transmission signal number-of-sequenceinformation because of transmitting another uplink control signal (forexample, scheduling request) in a subframe in which uplink controlchannel resource allocation is performed to transmit the transmissionsignal number-of-sequence information, it is possible to applyEmbodiments 1 to 4 as described above.

This example will be described using FIGS. 3 and 4 showing Embodiment 1.In addition, configurations of the base station apparatus and mobilestation apparatus are the same as in FIGS. 1 and 2. As in Embodiment 1,first, the mobile station apparatus transmits the transmission signalnumber-of-sequence information to the base station apparatus as feedbackin a subframe 1 first assigned uplink control channel resources.Subsequently, in subframes 4, 7 and 10 in which next uplink controlchannel allocation is performed, the mobile station apparatus transmitsto the base station apparatus the reception quality information and thetransmission signal preprocessing information based on the transmissionsignal number-of-sequence information (=3) transmitted to the basestation apparatus in the subframe 1. Embodiment 5 does not consider DRX.

When such a situation occurs that the mobile station apparatus cannottransmit the transmission signal number-of-sequence information (=2)because of transmitting another uplink control signal (for example,scheduling request) at the timing of a subframe 13 in which the basestation apparatus performs uplink control channel resource allocation soas to transmit the transmission signal number-of-sequence information,the mobile station apparatus performs feedback of the transmissionsignal number-of-sequence information (=2) in a subframe 16 in whichuplink control channel resource allocation is next performed. As well asEmbodiment 1, although the subframe 16 is originally the timing offeedback of the reception quality information and transmission signalpreprocessing information, the mobile station apparatus does not performthe feedback because of transmitting the transmission signalnumber-of-sequence information. Then, in subframes 19 and 22 in whichnext uplink control channel allocation is performed, the mobile stationapparatus transmits to the base station apparatus the reception qualityinformation and transmission signal preprocessing information based onthe transmission signal number-of-sequence information (=2) that is thefeedback in the subframe 16.

Similarly, when such a situation occurs that the mobile stationapparatus cannot transmit the transmission signal number-of-sequenceinformation (for example, in the case of transmitting another uplinkcontrol signal), as described in Embodiment 2, the mobile stationapparatus is capable of transmitting feedback of the reception qualityinformation and transmission signal preprocessing information to thebase station apparatus while setting the number of transmissionsequences at a predetermined value until next feedback of thetransmission signal number-of-sequence information is performed in asubframe in which uplink control channel resource allocation isperformed.

Further, when such a situation occurs that the mobile station apparatuscannot transmit the transmission signal number-of-sequence information(for example, in the case of transmitting another uplink controlsignal), as described in Embodiment 3, the mobile station apparatus doesnot perform feedback of the reception quality information andtransmission signal preprocessing information until next feedback of thetransmission signal number-of-sequence information is performed in asubframe in which uplink control channel resource allocation isperformed, and the base station apparatus is capable of performingdownlink data transmission using the predetermined number oftransmission signal sequences.

Furthermore, when such a situation occurs that the mobile stationapparatus cannot transmit the transmission signal number-of-sequenceinformation (for example, in the case of transmitting another uplinkcontrol signal), as described in Embodiment 4, during a period until themobile station apparatus performs next feedback of the transmissionsignal number-of-sequence information in a subframe in which uplinkcontrol channel resource allocation is performed, even when the mobilestation apparatus transmits the reception quality information andtransmission signal preprocessing information as feedback, the basestation apparatus abandons (disables) the information and is capable oftransmitting downlink data in predetermined form.

Thus, according to the mobile communication system according toEmbodiment 5 of the invention, when such a situation occurs that themobile station apparatus cannot transmit the transmission signalnumber-of-sequence information due to the reason (for example,transmission of another uplink control signal) except DRX, the basestation apparatus is capable of knowing the correct transmission signalnumber-of-sequence information, and performing appropriate downlinkcommunications based on the subsequently transmitted reception qualityinformation and transmission signal preprocessing information.

In aforementioned Embodiments 1 to 5, scheduling is performed so as totransmit the reception quality information and transmission signalpreprocessing information at the same timing, but it is possible toperform the similar processing also in the case of performing schedulingso that the information is in different subframes.

(A) A mobile station apparatus according to this Embodiment is a mobilestation apparatus having a plurality of antennas to perform radiocommunications with a base station apparatus using all or a part of theplurality of antennas, has a feedback information generating sectionthat generates feedback information including reception qualityinformation indicative of reception quality, transmission signalpreprocessing information used by the base station apparatus inperforming preprocessing on a transmission signal, and transmissionsignal number-of-sequence information indicative of multiplexedtransmission signal sequences, and a transmitting section thatperiodically transmits the generated feedback information to the basestation apparatus, and is characterized in that when the transmittingsection does not transmit the transmission signal number-of-sequenceinformation with communication resources periodically allocated from thebase station apparatus so as to transmit the transmission signalnumber-of-sequence information, the transmitting section transmits thetransmission signal number-of-sequence information to the base stationapparatus with communication resources enabling transmission of thefeedback information allocated from the base station apparatussubsequently to the communication resources.

Thus, when the mobile station apparatus does not transmit thetransmission signal number-of-sequence information with communicationresources periodically allocated by the base station apparatus so as totransmit the transmission signal number-of-sequence information, themobile station apparatus transmits the transmission signalnumber-of-sequence information to the base station apparatus withcommunication resources enabling transmission of the feedbackinformation allocated from the base station apparatus subsequently tothe communication resources. Therefore, for example, even when themobile station apparatus cannot transmit feedback of the transmissionsignal number-of-sequence information to the base station apparatusbecause a subframe that is the transmission timing of transmissionsignal number-of-sequence information is in a period of Non-active Timeof DRX, the mobile station apparatus is capable of performing thefeedback in a subframe with uplink control channel resource allocationsubsequent to the end of the Non-active Time of DRX. By this means, thebase station apparatus is capable of knowing the correct transmissionsignal number-of-sequence information after the end of the Non-activeTime of DRX, and performing appropriate downlink communication resourceallocation based on the subsequently transmitted reception qualityinformation and transmission signal preprocessing information.

(B) Further, a mobile station apparatus according to this Embodiment isa mobile station apparatus having a plurality of antennas to performradio communications with a base station apparatus using all or a partof the plurality of antennas, has a feedback information generatingsection that generates feedback information including reception qualityinformation indicative of reception quality, transmission signalpreprocessing information used by the base station apparatus inperforming preprocessing on a transmission signal, and transmissionsignal number-of-sequence information indicative of multiplexedtransmission signal sequences, and a transmitting section thatperiodically transmits the generated feedback information to the basestation apparatus, and is characterized in that when the transmittingsection does not transmit the transmission signal number-of-sequenceinformation with communication resources periodically allocated from thebase station apparatus so as to transmit the transmission signalnumber-of-sequence information, the feedback information generatingsection generates the reception quality information and transmissionsignal preprocessing information corresponding to the beforehand definednumber of transmission signal sequences during a period untilcommunication resources periodically allocated from the base stationapparatus so as to transmit the transmission signal number-of-sequenceinformation subsequent to the communication resources, and thetransmitting section transmits at least one of the transmission equalityinformation and transmission signal preprocessing informationcorresponding to the beforehand defined number of transmission signalsequences to the base station apparatus.

Thus, when the mobile station apparatus does not transmit thetransmission signal number-of-sequence information with communicationresources periodically allocated from the base station apparatus so asto transmit the transmission signal number-of-sequence information, themobile station apparatus transmits at least one of the transmissionequality information and transmission signal preprocessing informationcorresponding to the beforehand defined number of transmission signalsequences to the base station apparatus during a period untilcommunication resources periodically allocated from the base stationapparatus so as to transmit the transmission signal number-of-sequencesubsequent to the communication resources. Therefore, for example, evenwhen the mobile station apparatus cannot perform feedback of thetransmission signal number-of-sequence information because a subframethat is the transmission timing of transmission signalnumber-of-sequence information is in a period of Non-active Time of DRX,the mobile station apparatus is capable of performing feedback of thereception quality information and transmission preprocessing informationcorresponding to a predetermined fixed value of the transmission signalnumber-of-sequence information until next feedback of subsequenttransmission signal number-of-sequence information from the mobilestation apparatus after the end of the Non-active Time of DRX. By thismeans, the base station apparatus is capable of performing appropriatedownlink communication resource allocation.

(C) Further, a mobile station apparatus according to this Embodiment isa mobile station apparatus having a plurality of antennas to performradio communications with a base station apparatus using all or a partof the plurality of antennas, has a feedback information generatingsection that generates feedback information including reception qualityinformation indicative of reception quality, transmission signalpreprocessing information used by the base station apparatus inperforming preprocessing on a transmission signal, and transmissionsignal number-of-sequence information indicative of multiplexedtransmission signal sequences, and a transmitting section thatperiodically transmits the generated feedback information to the basestation apparatus, and is characterized in that when the transmittingsection does not transmit the transmission signal number-of-sequenceinformation with communication resources periodically allocated from thebase station apparatus so as to transmit the transmission signalnumber-of-sequence information, the transmitting section haltstransmission of the feedback information for a period untilcommunication resources periodically allocated from the base stationapparatus so as to transmit the transmission signal number-of-sequenceinformation subsequent to the communication resources.

Thus, when the mobile station apparatus does not transmit thetransmission signal number-of-sequence information with communicationresources periodically allocated from the base station apparatus so asto transmit the transmission signal number-of-sequence information, themobile station apparatus halts transmission of the feedback informationduring a period until communication resources periodically allocatedfrom the base station apparatus so as to transmit the transmissionsignal number-of-sequence information subsequent to the communicationresources. Therefore, even when the mobile station apparatus cannotperform feedback of the transmission signal number-of-sequenceinformation because a subframe that is the transmission timing oftransmission signal number-of-sequence information is in a period ofNon-active Time of DRX, the mobile station apparatus does not performfeedback of the reception quality information and transmission signalpreprocessing information for a period during which the Non-active Timeof DRX ends and next feedback is performed on the transmission signalnumber-of-sequence information, and the base station apparatus iscapable of performing downlink communication resource allocation inpredetermined form. By this means, downlink communications can beperformed as normally as possible.

(D) Further, a base station apparatus according to this Embodiment is abase station apparatus having a plurality of antennas to perform radiocommunications with a mobile station apparatus using all or a part ofthe plurality of antennas, has a scheduler section that periodicallyallocates communication resources to the mobile station apparatus inorder for the mobile station apparatus to transmit transmission signalnumber-of-sequence information, and a transmission signalnumber-of-sequence information control section that determines thenumber of transmission signal sequences at least based on thetransmission signal number-of-sequence information transmitted from themobile station apparatus, and is characterized in that when the mobilestation apparatus does not transmit the transmission signalnumber-of-sequence information with the communication resources, thetransmission signal number-of-sequence information control sectiondetermines the number of transmission signal sequences based oninformation transmitted with communication resources enablingtransmission of the feedback information allocated subsequently to thecommunication resources.

Thus, when the mobile station apparatus does not transmit thetransmission signal number-of-sequence information with thecommunication resources, since the number of transmission signalsequences is determined based on information transmitted withcommunication resources enabling transmission of the feedbackinformation allocated subsequently to the communication resources.Therefore, for example, even when the mobile station apparatus cannottransmit feedback of the transmission signal number-of-sequenceinformation to the base station apparatus because a subframe that is thetransmission timing of transmission signal number-of-sequenceinformation is in a period of Non-active Time of DRX, the feedback canbe given in a subframe in which uplink control channel resourceallocation is performed subsequently to the end of the Non-active Timeof DRX. By this means, the base station apparatus is capable of knowingthe correct transmission signal number-of-sequence information after theend of the Non-active Time of DRX, and performing appropriate downlinkcommunication resource allocation based on the subsequently transmittedreception quality information and transmission signal preprocessinginformation.

(E) Further, a base station apparatus according to this embodiment is abase station apparatus having a plurality of antennas to perform radiocommunications with a mobile station apparatus using all or a part ofthe plurality of antennas, has a scheduler section that periodicallyallocates communication resources to the mobile station apparatus inorder for the mobile station apparatus to transmit transmission signalnumber-of-sequence information, and a transmission signalnumber-of-sequence information control section that determines thenumber of transmission signal sequences at least based on thetransmission signal number-of-sequence information transmitted from themobile station apparatus, and is characterized in that when the mobilestation apparatus does not transmit the transmission signalnumber-of-sequence information with the communication resources, thetransmission signal number-of-sequence information control section usesthe beforehand defined number of transmission signal sequences as thenumber of transmission signal sequences until communication resourcesperiodically allocated to transmit the transmission signalnumber-of-sequence information subsequent to the communicationresources.

Thus, when the mobile station apparatus does not transmit thetransmission signal number-of-sequence information with thecommunication resources, the beforehand defined number of transmissionsignal sequences is used as the number of transmission signal sequencesuntil communication resources periodically allocated to transmit thetransmission signal number-of-sequence information subsequent to thecommunication resources. Therefore, for example, even when the mobilestation apparatus cannot perform feedback of the transmission signalnumber-of-sequence information because a subframe that is thetransmission timing of transmission signal number-of-sequenceinformation is in a period of Non-active Time of DRX, it is possible touse the reception quality information and transmission preprocessinginformation corresponding to a predetermined fixed value of thetransmission signal number-of-sequence information until feedback ofsubsequent transmission signal number-of-sequence information is givenfrom the mobile station apparatus after the end of the Non-active Timeof DRX. By this means, the base station apparatus is capable ofperforming appropriate downlink communication resource allocation.

(F) Further, a base station apparatus according to this Embodiment is abase station apparatus having a plurality of antennas to perform radiocommunications with a mobile station apparatus using all or a part ofthe plurality of antennas, has a scheduler section that periodicallyallocates communication resources to the mobile station apparatus inorder for the mobile station apparatus to transmit transmission signalnumber-of-sequence information, and a transmission signalnumber-of-sequence information control section that determines thenumber of transmission signal sequences at least based on thetransmission signal number-of-sequence information transmitted from themobile station apparatus, and is characterized in that when the mobilestation apparatus does not transmit the transmission signalnumber-of-sequence information with the communication resources, thetransmission signal number-of-sequence information control sectionabandons feedback information transmitted from the mobile stationapparatus until communication resources periodically allocated totransmit the transmission signal number-of-sequence informationsubsequent to the communication resources.

Thus, when the mobile station apparatus does not transmit thetransmission signal number-of-sequence information with thecommunication resources, feedback information transmitted from themobile station apparatus is abandoned for a period until communicationresources periodically allocated to transmit the transmission signalnumber-of-sequence information subsequent to the communicationresources. Therefore, when the mobile station apparatus cannot performfeedback of the transmission signal number-of-sequence informationbecause a subframe that is the transmission timing of transmissionsignal number-of-sequence information is in a period of Non-active Timeof DRX, even in the case that the mobile station apparatus performsfeedback of the reception quality information and transmission signalpreprocessing information for a period during which the Non-active Timeof DRX ends and next feedback is performed on the transmission signalnumber-of-sequence information, the base station apparatus disables theinformation and is capable of performing downlink communication resourceallocation in predetermined form. By this means, downlink communicationscan be performed as normally as possible.

(G) Further, a communication method according to this Embodiment is acommunication method in which a mobile station apparatus periodicallytransmits feedback information including reception quality informationindicative of reception quality, transmission signal preprocessinginformation used in performing preprocessing on a transmission signal,and transmission signal number-of-sequence information indicative ofmultiplexed transmission signal sequences to a base station apparatus,and the base station apparatus receives the feedback informationperiodically from the mobile station apparatus and allocatescommunication resources to the mobile station apparatus based on thereceived feedback information, and is characterized in that when themobile station apparatus does not transmit the transmission signalnumber-of-sequence information with communication resources periodicallyallocated from the base station apparatus so as to transmit thetransmission signal number-of-sequence information, the mobile stationapparatus transmits the transmission signal number-of-sequenceinformation to the base station apparatus with communication resourcesenabling transmission of the feedback information allocated from thebase station apparatus subsequently to the communication resources, andthat when the mobile station apparatus does not transmit thetransmission signal number-of-sequence information with communicationresources periodically allocated to transmit the transmission signalnumber-of-sequence information, the base station apparatus receives thetransmission signal number-of-sequence information transmitted withcommunication resources enabling transmission of the feedbackinformation allocated subsequently to the communication resources, anddetermines the number of transmission signal sequences.

Thus, when the mobile station apparatus does not transmit thetransmission signal number-of-sequence information with communicationresources periodically allocated from the base station apparatus so asto transmit the transmission signal number-of-sequence information, themobile station apparatus transmits the transmission signalnumber-of-sequence information to the base station apparatus withcommunication resources enabling transmission of the feedbackinformation allocated from the base station apparatus subsequently tothe communication resources. Therefore, for example, even when themobile station apparatus cannot transmit feedback of the transmissionsignal number-of-sequence information to the base station apparatusbecause a subframe that is the transmission timing of transmissionsignal number-of-sequence information is in a period of Non-active Timeof DRX, the mobile station apparatus is capable of performing thefeedback in a subframe in which uplink control channel resourceallocation is performed subsequently to the end of the Non-active Timeof DRX. By this means, the base station apparatus is capable of knowingthe correct transmission signal number-of-sequence information after theend of the Non-active Time of DRX, and performing appropriate downlinkcommunication resource allocation based on the subsequently transmittedreception quality information and transmission signal preprocessinginformation.

(H) Further, a communication system according to this Embodiment ischaracterized by being comprised of the mobile station apparatus asdescribed in (A) and the base station apparatus as described in (D), themobile station apparatus as described in (B) and the base stationapparatus as described in (E), or the mobile station apparatus asdescribed in (C) and the base station apparatus as described in (F).

According to this constitution, for example, after the end of Non-activeTime of DRX in the mobile station apparatus, the base station apparatusis capable of knowing the correct transmission signal number-of-sequenceinformation, and performing appropriate downlink communication resourceallocation based on the subsequently transmitted reception qualityinformation and transmission signal preprocessing information.

In the foregoing, each of the Embodiments of the invention is describedspecifically with reference to drawings, but specific constitutions arenot limited to the above-mentioned Embodiments, and designs and othersin the scope without departing from the subject matter of the inventionare included in the scope of the claims.

1. A mobile communication system in which a mobile station apparatusperiodically transmits transmission signal number-of-sequenceinformation and reception quality information calculated based on thetransmission signal number-of-sequence information to a base stationapparatus, wherein the mobile station apparatus calculates the receptionquality information based on the predetermined number of transmissionsignal sequences when the transmission signal number-of-sequenceinformation is not transmitted to the base station apparatus, and thebase station apparatus processes the reception quality information basedon the predetermined number of transmission signal sequences when thetransmission signal number-of-sequence information is not transmitted.2. The mobile communication system according to claim 1, wherein thepredetermined number of transmission signal sequences is the minimumnumber of transmission signal sequences.
 3. The mobile communicationsystem according to claim 1, wherein the predetermined number oftransmission signal sequences is the maximum number of transmissionsignal sequences.
 4. A mobile communication system in which a mobilestation apparatus periodically transmits transmission signalnumber-of-sequence information and transmission signal preprocessinginformation calculated based on the transmission signalnumber-of-sequence information to a base station apparatus, wherein themobile station apparatus calculates the transmission signalpreprocessing information based on the predetermined number oftransmission signal sequences when the transmission signalnumber-of-sequence information is not transmitted to the base stationapparatus, and the base station apparatus processes the transmissionsignal preprocessing information based on the predetermined number oftransmission signal sequences when the transmission signalnumber-of-sequence information is not transmitted.
 5. The mobilecommunication system according to claim 4, wherein the predeterminednumber of transmission signal sequences is the minimum number oftransmission signal sequences.
 6. The mobile communication systemaccording to claim 4, wherein the predetermined number of transmissionsignal sequences is the maximum number of transmission signal sequences.7. A base station apparatus for periodically receiving transmissionsignal number-of-sequence information and reception quality informationcalculated in a mobile station apparatus based on the transmissionsignal number-of-sequence information from the mobile station apparatus,comprising: a section that processes the reception quality informationbased on the predetermined number of transmission signal sequences whenthe transmission signal number-of-sequence information is nottransmitted.
 8. The base station apparatus according to claim 7, whereinthe predetermined number of transmission signal sequences is the minimumnumber of transmission signal sequences.
 9. The base station apparatusaccording to claim 7, wherein the predetermined number of transmissionsignal sequences is the maximum number of transmission signal sequences.10. A base station apparatus for periodically receiving transmissionsignal number-of-sequence information and transmission signalpreprocessing information that is calculated in a mobile stationapparatus based on the transmission signal number-of-sequenceinformation from the mobile station apparatus, comprising: a sectionthat processes the transmission signal preprocessing information basedon the predetermined number of transmission signal sequences when thetransmission signal number-of-sequence information is not transmitted.11. The base station apparatus according to claim 10, wherein thepredetermined number of transmission signal sequences is the minimumnumber of transmission signal sequences.
 12. The base station apparatusaccording to claim 10, wherein the predetermined number of transmissionsignal sequences is the maximum number of transmission signal sequences.13. A mobile station apparatus for periodically transmittingtransmission signal number-of-sequence information and reception qualityinformation calculated based on the transmission signalnumber-of-sequence information to a base station apparatus, comprising:a section that calculates the reception quality information based on thepredetermined number of transmission signal sequences when thetransmission signal number-of-sequence information is not transmitted.14. The mobile station apparatus according to claim 13, wherein thepredetermined number of transmission signal sequences is the minimumnumber of transmission signal sequences.
 15. The mobile stationapparatus according to claim 13, wherein the predetermined number oftransmission signal sequences is the maximum number of transmissionsignal sequences.
 16. A mobile station apparatus for periodicallytransmitting transmission signal number-of-sequence information andtransmission signal preprocessing information calculated based on thetransmission signal number-of-sequence information to a base stationapparatus, comprising: a section that calculates the transmission signalpreprocessing information based on the predetermined number oftransmission signal sequences when the transmission signalnumber-of-sequence information is not transmitted.
 17. The mobilestation apparatus according to claim 16, wherein the predeterminednumber of transmission signal sequences is the minimum number oftransmission signal sequences.
 18. The mobile station apparatusaccording to claim 16, wherein the predetermined number of transmissionsignal sequences is the maximum number of transmission signal sequences.